Secondary battery pack

ABSTRACT

A battery pack including a battery cell having an anode and cathode terminal at one face having a sealed surplus portion and a protection circuit module (PCM) connected to the cell via the anode and cathode terminal, the PCM including a board having a protection circuit thereon, the board being provided with an anode and cathode terminal connection part connected to the anode and cathode terminal, respectively, and a PCM case configured to receive the board through an open face thereof so that the PCM case surrounds the board. The board is coupled to the anode and cathode terminal of the cell via the anode and cathode terminal connection part, the board is disposed in the PCM case in a state in which the board is parallel to the cell, and the PCM case, in which the board is disposed, is mounted to the sealed surplus portion of the cell.

CROSS REFERENCE TO RELATED APPLICATIONS

This non-provisional application is a Continuation of InternationalApplication No. PCT/KR2012/006128 filed on Aug. 1, 2012, which claimsthe benefit of Korean Patent Application Nos. 10-2011-0078989 filed inKorea on Aug. 9, 2011 and 10-2012-0014792 filed in Korea on Feb. 14,2012. The entire contents of all of the above applications are herebyincorporated by reference.

TECHNICAL FIELD

The present invention relates to a secondary battery pack.

BACKGROUND ART

As mobile devices have been increasingly developed, and the demand forsuch mobile devices has increased, the demand for secondary batterieshas also sharply increased. Among such secondary batteries is a lithiumsecondary battery exhibiting high energy density and operating voltageand excellent preservation and service-life characteristics, which hasbeen widely used as an energy source for various electronic products aswell as various kinds of mobile devices.

Depending upon kinds of devices in which secondary batteries are used,the secondary batteries may be configured to have a detachable typestructure in which the secondary batteries can be easily inserted intoand removed from external devices or to have an embedded type structurein which the secondary batteries are embedded in the devices. Forexample, secondary batteries used in the conventional mobile devices areconfigured to have a detachable type structure in which it is possiblefor a user to insert or remove a battery into or from each device. Onthe other hand, secondary batteries used in devices, such as some mobilephones, tablet PCs, and smart pads, may be configured to have anembedded type structure.

Lithium secondary batteries are widely used as such secondary batteries.Each of the secondary batteries includes an anode terminal and a cathodeterminal electrically connected to a device, in which the secondarybattery is mounted, and a safety element to effectively control anabnormal state, such as overcharge or overcurrent, of the secondarybattery. Examples of the safety element may include a positivetemperature coefficient (PTC) element, a protection circuit module(PCM), a fuse, and a thermal cutoff (TCO) element.

Generally, a safety element, such as a PCM, is connected to a batterycell, including an anode terminal and a cathode terminal, via aconductive nickel plates by welding or soldering. For example, thenickel plates are connected to the electrode terminals of the batterycell by welding or soldering, a protection circuit board (PCB) isattached to one side of a double-sided tape, a protective tape isattached to the other side of the double-sided tape, and electrode tabsof the PCB and the nickel plates are connected to each other by weldingin a state in which the PCB is in tight contact with the battery cell.In this way, the PCM is connected to the battery cell to manufacture abattery pack.

It is required for the PCM to be maintained in electrical connectionwith the electrode terminals of the battery cell and, at the same time,to be electrically isolated from other parts of the battery cell. Tothis end, insulative tapes are attached to various members, includingthe PCM. In addition, a sealed portion of a battery case is partiallybent, and an insulative tape is attached thereon or a barcode is printedthereon. That is, the process is very complicated.

Since a plurality of insulative tapes or parts is required to achievesafe connection between the safety element and the battery cell asdescribed above, a battery pack assembly process is complicated, andmanufacturing cost is increased. Also, when external impact is appliedto a battery pack, the PCM may be damaged or dimensional stability maybe greatly lowered due to the use of the insulative tapes, which exhibitlow mechanical strength.

DISCLOSURE Technical Problem

It is an object of the present invention to provide a secondary batterypack that is capable of covering a protection circuit board of asecondary battery cell using an electrically insulative case, therebyprotecting the protection circuit board from external impact, insulatingthe protection circuit board, and preventing electrode terminals of thesecondary battery cell from being exposed outside.

It is another object of the present invention to provide a secondarybattery pack that is capable of reducing the number of parts necessaryto constitute the battery pack, thereby simplify an assembly process andexhibiting excellent structural stability.

It is another object of the present invention to provide a secondarybattery pack configured to have a structure in which a protectioncircuit module including a protection circuit board and a case, in whichthe protection circuit board is disposed, is mounted to an outercircumference of a battery cell, thereby providing maximum capacity inthe same standard.

It is a further object of the present invention to provide a protectioncircuit module that is capable of a protection circuit module that iscapable of protecting a safety element from external impact, exhibitingdimensional stability, and preventing wrinkles from being formed at anouter face of a battery pack.

Technical Solution

A secondary battery pack according to an embodiment of the presentinvention includes a battery cell having an anode terminal and a cathodeterminal formed at one face having a sealed surplus portion and aprotection circuit module (PCM) electrically connected to the batterycell via the anode terminal and the cathode terminal.

In this embodiment, the PCM may include a board having a protectioncircuit formed thereon, the board being provided with an anode terminalconnection part and a cathode terminal connection part connected to theanode terminal and the cathode terminal, respectively, and a PCM caseconfigured to receive the board through an open face thereof so that thePCM case surrounds the board.

In this embodiment, the board may be coupled to the anode terminal andthe cathode terminal of the battery cell via the anode terminalconnection part and the cathode terminal connection part, the board maybe disposed in the PCM case in a state in which the board is parallel tothe battery cell, and the PCM case, in which the board is disposed, maybe mounted to the sealed surplus portion of the battery cell.

In this embodiment, the PCM may further include an electricallyinsulative lid to close the open face of the PCM case.

In this embodiment, the PCM case and the lid may be coupled to eachother through an assembly type fastening structure. The PCM case may beprovided with at least one fastening groove for coupling with the lid,and the lid may be provided with at least one fastening protrusioncorresponding to the at least one fastening groove of the PCM case.

In this embodiment, the battery cell may be a plate-shaped battery cell,and the anode terminal and the cathode terminal may be plate-shapedconductive members.

In this embodiment, the board may further include an external input andoutput terminal. The external input and output terminal may be formed atthe board at which the anode terminal connection part and the cathodeterminal connection part are formed via an interconnection part.

Also, the external input and output terminal may be formed on the boardat which the anode terminal connection part and the cathode terminalconnection part are formed.

In this embodiment, the external input and output terminal may be formedat the other face of the board at which the anode terminal connectionpart and the cathode terminal connection part are formed.

In this embodiment, the PCM case may further include an opening, throughwhich the external input and output terminal is drawn, formed at a faceadjacent to the open face thereof. An example of the opening may be aslit type opening.

In this embodiment, the secondary battery pack may further include aninsulative tape additionally attached to an electrode terminal exposureregion of the sealed surplus portion. The insulative tape may be, forexample, a double-sided tape.

In this embodiment, the secondary battery pack may further include aninsulative tape additionally attached to at least one of outer faces ofthe PCM case.

In this embodiment, the battery cell may be configured to have astructure in which an electrode assembly, including cathodes, anodes,and separators respectively disposed between the cathodes and theanodes, is disposed in a battery case made of a laminate sheet includinga metal layer and a resin layer in a sealed state.

In this embodiment, the board may be disposed in the PCM case in a statein which the board is parallel to the battery cell in an extensiondirection identical to an extension direction of the sealed surplusportion.

In this embodiment, the secondary battery pack may further include anickel plate additionally mounted to one face of the cathode terminal,to which the cathode terminal connection part of the board is coupled,by ultrasonic welding.

In this embodiment, the secondary battery pack may further include alabel to cover the battery cell. The label may be configured to have astructure to cover sealed outer circumferences of the battery cell.

A protection circuit module according to another embodiment of thepresent invention includes a protection circuit board having an anodeterminal connection part and a cathode terminal connection partconnected to an anode terminal and a cathode terminal of a battery cell,respectively, and a PCM case configured to receive the protectioncircuit board through an open face thereof.

In the protection circuit module according to this embodiment, theprotection circuit board may be coupled to the anode terminal and thecathode terminal of the battery cell via the anode terminal connectionpart and the cathode terminal connection part, the board may be disposedin the PCM case in a state in which the board is parallel to the batterycell, and the PCM case, in which the board is disposed, may be mountedto the sealed surplus portion of the battery cell.

In the protection circuit module according to this embodiment, anelectrically insulative lid may be mounted to the PCM case to close theopen face of the PCM case.

In the protection circuit module according to this embodiment, the PCMcase and the lid may be coupled to each other through an assembly typefastening structure. The PCM case may be provided with at least onefastening groove for coupling with the lid, and the lid may be providedwith at least one fastening protrusion corresponding to the at least onefastening groove of the PCM case. Alternatively, a person havingordinary skill in the art to which the present invention pertains willappreciate that the PCM case may be provided with at least one fasteningprotrusion (for example, hook), and the lid may be provided with atleast one fastening groove corresponding to the at least one fasteningprotrusion of the PCM case, or fastening protrusions and fasteninggrooves may be alternately formed at the PCM case and the lid. That is,the fastening structure to couple the PCM case and the lid is notparticularly restricted so long as the PCM case and the lid can becoupled to each other.

In the protection circuit module according to this embodiment, the PCMcase may be configured to have a hollow box structure opened at one facethereof.

In the protection circuit module according to this embodiment, theprotection circuit board may further include an external input andoutput terminal coupled to the board at which the anode terminalconnection part and the cathode terminal connection part are formed viaan interconnection part. The PCM case may further include an opening,through which the interconnection part extends, formed at a faceadjacent to the open face thereof. Also, the PCM case may include a slittype opening.

A method of manufacturing a secondary battery pack according to anotherembodiment of the present invention includes a step of forming a batterycell configured to have a structure in which an electrode assembly,including cathodes, anodes, and separators respectively disposed betweenthe cathodes and the anodes, is disposed in a battery case in a sealedstate, one of sealed outer circumferences of the battery cell having asurplus portion, a step of receiving a board into a case opened at oneface thereof in an extension direction identical to an extensiondirection of the sealed surplus portion in a state in which the board isparallel to the battery cell, a step of mounting the case to the sealedsurplus portion of the battery cell, and a step of mounting anelectrically insulative lid to the PCM case to close the open face ofthe PCM case.

A secondary battery pack according to a further embodiment of thepresent invention includes a battery cell having an anode terminal and acathode terminal formed at one face having a sealed surplus portion anda protection circuit module (PCM) electrically connected to the batterycell via the anode terminal and the cathode terminal.

In this embodiment, the PCM may include a board having a protectioncircuit formed thereon, the board being provided with an anode terminalconnection part and a cathode terminal connection part connected to theanode terminal and the cathode terminal, respectively, and a PCM caseconfigured to receive the board through an open face thereof so that thePCM case surrounds the board.

In this embodiment, the board may be coupled to the anode terminal andthe cathode terminal of the battery cell via the anode terminalconnection part and the cathode terminal connection part, the board maybe disposed in the PCM case in a state in which the board isperpendicular to the battery cell, and the PCM case, in which the boardis disposed, may be mounted to the sealed surplus portion of the batterycell, and the PCM may further include an electrically insulative lid toclose the open face of the PCM case.

Advantageous Effects

The secondary battery pack according to the present invention isconfigured to have a structure in which the PCM, in which the PCB isdisposed in the PCM case, is mounted to the sealed surplus portion ofthe battery cell. Consequently, it is possible to effectively protectthe PCM and to greatly reduce the number of parts constituting thesecondary battery pack, thereby greatly improving manufacturingefficiency, as compared with the conventional internal type secondarybattery pack.

Also, the secondary battery pack according to the present invention isconfigured to have a structure in which the PCB is mounted in the PCMcase in an insertion fashion. Consequently, it is possible to greatlyreduce the number of parts constituting the secondary battery pack,thereby greatly improving manufacturing efficiency, thereby easilymanufacturing the secondary battery pack, relatively reducing a defectrate, and configuring the secondary battery pack so that the secondarybattery pack has no wrinkles formed at the outer face thereof, i.e. aneat and clean external appearance, as compared with the conventionalinternal type secondary battery pack in which the PCM is insulated usinga tape.

In addition, the secondary battery pack according to the presentinvention is configured to have a structure in which the PCB is mountedto the sealed surplus portion of the battery cell in a direction facingthe upper end of the main body of the battery cell in a state in whichthe PCB is erected perpendicularly to the battery cell. Consequently, itis possible to reduce the length of the sealed surplus portion and toincrease the capacity of the secondary battery pack per unit volume, ascompared with the structure in which the PCB is mounted to the sealedsurplus portion in parallel.

BRIEF DESCRIPTION OF DRAWINGS

The above and other objects, features and other advantages of thepresent invention will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is an exploded perspective view of a secondary battery packaccording to an embodiment of the present invention;

FIGS. 2 to 9 are perspective views showing a method of manufacturing thesecondary battery pack of FIG. 1;

FIG. 10 is an enlarged perspective view showing “A” region of FIG. 8;and

FIG. 11 is a perspective view of a secondary battery pack according toanother embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Now, exemplary embodiments of the present invention will be described indetail with reference to the accompanying drawings. It should be noted,however, that the embodiments will be described only for a betterunderstanding of the present invention, and therefore, the scope of thepresent invention is not limited by the illustrated embodiments.

A secondary battery pack according to an embodiment of the presentinvention includes a battery cell having four sealed outercircumferences and a safety element mounted to a sealed outercircumference having a surplus portion, which is one of the outercircumferences. A safety element according to an embodiment of thepresent invention may include a first safety element and a second safetyelement. The first safety element may be a protection circuit, and thesecond safety element may be a positive temperature coefficient (PTC)element, a fuse, or a thermal cutoff (TCO) element. Also, the secondsafety element may be mounted in a protection circuit module (PCM) inthe form of a part.

The safety element according to the embodiment of the present inventionmay be a PCM. The PCM may include a protection circuit board and a case,in which the protection circuit board is disposed. In addition, the PCMmay also include an electrically insulative lid to close an open face ofthe case. For the convenience of description, a PCM will be described asbeing adopted as the safety element, and the PCM will be described asincluding a protection circuit board (PCB) in this specification, towhich, however, the safety element according to the embodiment of thepresent invention is not limited.

Hereinafter, a secondary battery pack according to an embodiment of thepresent invention will be described with reference to FIG. 1. FIG. 1typically shows an exploded perspective view of a secondary battery packaccording to an embodiment of the present invention.

Referring to FIG. 1, a secondary battery pack 700 may include an anodeterminal 120, a cathode terminal 110, a battery cell 100, a PCM 500, anda label 400.

A battery cell 100 according to an embodiment of the present inventionis a pouch-shaped battery cell configured so that an electrode assemblyof a cathode/separator/anode structure is disposed in a battery casemade of a laminate sheet including a metal layer and a resin layer in asealed state, to which, however, the battery cell according to theembodiment of the present invention is not limited.

Referring to FIG. 1, the battery cell 100 includes a sealed surplusportion 130 formed at one face thereof and an anode terminal 120 and acathode terminal 110 exposed to the sealed surplus portion 130. The term‘face’ used in this specification indicates an arbitrary face of atetrahedron with four faces, and is understood as including a side, asection, or an end. Also, in this specification, a sealed portion havinga surplus space formed at one of the sealed outer circumferences formedwhen an electrode assembly is disposed in a battery case made of alaminate sheet in a sealed state is referred to as a sealed surplusportion 130. However, a person having ordinary skill in the art to whichthe present invention pertains will appreciate that the sealed surplusportion may be replaced by terms, such as a thermal welded surplusportion and a sealed terrace, as long as the specified terms have thesame meaning as the sealed surplus portion.

An electrically insulative lid 600 according to an embodiment of thepresent invention is configured to have a structure to close an openface of a PCM case 300. As show in FIG. 1, the electrically insulativelid 600 is provided with hooks 610 corresponding to fastening grooves320 of the PCM case 300, and the PCM case 300 is provided with fasteninggrooves 320 corresponding to the hooks 610 of the electricallyinsulative lid 600. Consequently, the PCM case 300 and the electricallyinsulative lid 600 may be coupled to each other through an assembly typefastening structure.

An anode terminal 120 and a cathode terminal 110 according to anembodiment of the present invention are plate-shaped conductive members.The anode terminal 120 and the cathode terminal 110 are electricallyconnected to a PCB 200 of a PCM 500, which will hereinafter bedescribed.

A PCM 500 according to an embodiment of the present invention mayinclude a PCB 200 having a protection circuit, an electricallyinsulative PCM case 300, in which the PCB 200 is disposed, and anexternal input and output terminal 210.

Referring to FIG. 1, the PCB 200 is a board including a protectioncircuit. The PCB may be referred to as a protection circuit board orsimply a board. The PCB 200 may further include an anode terminalconnection part 220 connected to the anode terminal 120 of the batterycell 100 and a cathode terminal connection part 230 connected to thecathode terminal 110 of the battery cell 100 on the board in addition tothe protection circuit to control overcharge, overdischarge, andovercurrent of the battery. In addition to the protection circuit andthe two connection parts 220 and 230, the PCB 200 may further include anexternal input and output terminal 210 connected to the board via aninterconnection part 211 connected to one end of the board, as shown inFIG. 1.

An external input and output terminal 210 according to an embodiment ofthe present invention is not particularly restricted so long as theexternal input and output terminal can be electrically connected to thePCB 200 to supply current from an external device, such as a charger, tothe battery cell 100 or to supply current from the battery cell 100 toan external device, such as a mobile phone, an MP3 player, etc. Forexample, the external input and output terminal 210 may be configured tohave a plate structure having a connector 212 mounted to one endthereof.

Also, unlike the embodiment shown in FIG. 1, the external input andoutput terminal may be formed on the board on which the anode terminalconnection part and the cathode terminal connection part are formedwithout being connected to the PCB 200 via the interconnection part. Asecondary battery pack with the above-stated construction is shown inFIG. 11. In a case in which an external input and output terminal isformed on a PCB, openings are formed at a region of a PCM case 420 (seeFIG. 11), in which the PCB is disposed, corresponding to an externalinput and output terminal 430 (see FIG. 11). The external input andoutput terminal may be electrically connected to an external devicethrough the openings.

An anode terminal connection part 220 according to an embodiment of thepresent invention may include a part coupled to the PCB 200 and anextension part that can be bent when the anode terminal connection part220 is connected to the anode terminal 120 of the battery cell 100. Inthe same manner, a cathode terminal connection part 230 according to anembodiment of the present invention may include a part coupled to thePCB 200 and an extension part that can be bent when the cathode terminalconnection part 230 is connected to the cathode terminal 110 of thebattery cell 100.

As shown in FIG. 1, the external input and output terminal 210 accordingto the embodiment of the present invention is configured to have a platestructure having a connector 212 mounted to one end thereof, to which,however, the external input and output terminal 210 is not limited.Also, as shown in FIG. 1, the external input and output terminal 210 isconfigured to face in a direction opposite to a direction in which theanode terminal connection part 220 and the cathode terminal connectionpart 230 face, which, however, is only an example. According to anotherembodiment of the present invention, the external input and outputterminal 210 may be configured to face in the same direction as adirection in which the anode terminal connection part 220 and thecathode terminal connection part 230 face. Also, the external input andoutput terminal may be located at the cathode terminal connection partside.

A PCM case 300 according to an embodiment of the present invention isconfigured to have a hollow box structure opened at one face thereof sothat the PCB 200 can be mounted in the PCM case 300 through the openface. Consequently, dimensional stability of the PCM case 300 is high,and it is possible to greatly reduce mounting time and process. Here,the mounting time means time required for an assembly process of placingthe PCB 200 in the PCM case 300 and assembling the PCB 200 with the PCMcase 300. Reduction of the mounting time means reduction of timerequired for the assembly process, and therefore, it is possible togreatly simplify the process.

The PCM case 300 may have a size sufficient to receive and surround thePCB 200 mounted on the sealed surplus portion 130 of the battery cell100. In addition, in a case in which the PCB 200 includes the externalinput and output terminal 210 connected thereto via the interconnectionpart 211, as shown in FIG. 1, an opening, through which the externalinput and output terminal 210 is exposed, may be formed at a face of thePCM case 300 adjacent to the open face. For example, a slit type opening310 may be formed at the PCM case.

A secondary battery pack according to another embodiment of the presentinvention may be configured so that a safety element is further mountedbetween at least one of the electrode terminals, i.e. the anode terminaland/or the cathode terminal, of the battery cell and the PCB. In thiscase, the safety element may be disposed between, for example, the anodeterminal of the battery and the PCB. The safety element is mounted inthe PCM case together with the PCB so that the structural stability ofthe safety element is secured.

Consequently, it is possible to directly connect the cathode terminal ofthe battery cell to the cathode terminal connection part of the PCB andto connect one side of the safety element to the safety elementconnection part disposed on the same face of the PCB in a state in whichthe anode terminal is connected to the other side of the safety elementwithout shape deformation or further use of additional members, andtherefore, it is possible to stably mount the safety element, thestructural strength is low, to the PCB, thereby reducing a defect ratein a manufacturing process and improving manufacturing efficiency.

The safety element is a member which interrupts current when thetemperature of the battery cell is increased to secure safety. Forexample, the safety element may be a PTC element, the resistance ofwhich increases as the temperature of the battery cell is increased, ora fuse, which is broken when the temperature of the battery cell isincreased. However, the safety element is not limited to the PTC elementand the fuse.

Hereinafter, a method of manufacturing the secondary battery pack shownin FIG. 1 will be described with reference to FIGS. 2 to 10. FIGS. 2 to10 are various perspective views of a secondary battery packillustrating a method of manufacturing the secondary battery pack.

Referring first to FIG. 2, a surplus portion, i.e. a sealed surplusportion 130, is formed at one of sealed faces of a battery cell 100, andan anode terminal 120 and a cathode terminal 110 of the battery cell 100are disposed on the sealed surplus portion 130. The sealed surplusportion 130 has a size sufficient to receive a PCM 500, in which a PCB200 is coupled with a PCM case 300, and the size of the PCM case 300 maybe greater or less than that of the sealed surplus portion 130. A personhaving ordinary skill in the art to which the present invention pertainswill appreciate that the size of the PCM case 300 may be properlyadjusted based on the capacity and shape of the battery cell.

Subsequently, as shown in FIG. 2, a nickel plate 140 may be coupled to aportion of the cathode terminal 110, for example, by ultrasonic welding.In a case in which the nickel plate 140 is mounted to the cathodeterminal 110, it is possible to prevent deterioration of weldabilitybetween the cathode terminal, made of aluminum, of the battery cell anda PCB cathode terminal connection part made of nickel due to differentproperties.

Also, in another embedment of the present invention, as previouslydescribed, an additional safety element, such as a PTC element, may beselectively mounted between the anode terminal 120 and an anode terminalconnection part 220 to secure stability.

Subsequently, as shown in FIG. 3, the anode terminal connection part 220and a cathode terminal connection part 230 formed at the PCB 200 arewelded to the anode terminal 120 and the cathode terminal 110 of thebattery cell 100, respectively, for example, by spot welding. In a casein which the nickel plate 140 is welded to the cathode terminal 110 asshown in FIG. 2, the cathode terminal connection part 230 is welded tothe nickel plate 140.

Since the anode terminal connection part 220 and the cathode terminalconnection part 230 each include a part coupled to the PCB 200 and abendable extension part as described above, the anode terminalconnection part 220 and the cathode terminal connection part 230 of thePCB 200 may be coupled to the anode terminal 120 and the cathodeterminal 110 of the battery cell 100, respectively, by welding so thatthe PCB 200 is opposite to one face of the battery cell 100 at which thesealed surplus portion 130 is formed, as can be seen from FIG. 3.

Referring to FIG. 4 together with FIG. 1, after the anode terminalconnection part 220 and the cathode terminal connection part 230 arebent, an adhesive tape 160, serving as an insulation tape, may beattached to an electrode terminal exposure region of the sealed surplusportion 130 of the main body of the battery cell 100. In a case in whichthe insulation tape is further attached to the electrode terminalexposure region of the sealed surplus portion 130 as described above, itis possible to more effectively improve insulativity of the electrodeterminal exposure region. Also, in a case in which the insulation tapeis a double-sided tape, the double-side tape provides coupling forcebetween the PCM case and the sealed surplus portion when the PCM case ismounted to the PCB, thereby further improving structural stability.

In the embodiment of the present invention, the PCB 200, connected tothe battery cell 100 via the anode terminal connection part and thecathode terminal connection part, may be disposed in the PCM case in astate in which the PCB 200 is parallel to the battery cell 100, and maybe mounted to the sealed surplus portion of the battery cell 100. Here,the state in which the PCB 200 is parallel to the battery cell 100 maybe, for example, a state in which the anode terminal connection part 220and the cathode terminal connection part 230, connected to the anodeterminal and the cathode terminal of the battery cell, are disposed soas to face upward as shown in FIG. 4. In this case, as shown in FIG. 4,the PCB 200 may be spaced apart from the end of the battery cell atwhich the sealed surplus portion is formed by the connection lengthbetween the anode terminal and the anode terminal connection part andbetween the cathode terminal and the cathode terminal connection part inthe longitudinal direction so that the PCB 200 is parallel to the sealedsurplus portion.

In other words, in a case in which the PCB 200 is disposed in parallelto the battery cell, as shown in FIG. 4, the face of the PCB 200 atwhich the anode terminal connection part 220 and the cathode terminalconnection part 230 are located, faces upward with the result that twowidest ones of the four faces constituting the external appearance ofthe PCB 200 face upward and downward. Also, since the two widest ones ofthe four faces constituting the external appearance of the PCB 200 faceupward and downward, the two widest faces of the PCB 200 and two widestfaces of the battery cell 100 are disposed so as to face in the samedirections. Consequently, that the PCB 200 is disposed in parallel tothe battery cell 100 may be understood as including the above-mentionedpositional relationship.

Referring to FIG. 5, the board may be disposed in the PCM case in astate in which the board is parallel to the battery cell in an extensiondirection identical to an extension direction of the sealed surplusportion. As previously described in connection with FIG. 1, the PCM case300 is opened at one face thereof so that the PCM case 300 receives thePCB 200 through the open face. Also, in a case in which the externalinput and output terminal 210 is connected to the connection parts ofthe PCB 200 via the interconnection part as shown in FIG. 1, an opening,e.g. a slit type opening 310, may be formed at one face of the PCM case300 corresponding to the interconnection part 211 of the PCB 200 so thatthe external input and output terminal 210 is exposed outside. Since theinterconnection part 211 of the PCB 200 extends through the slit typeopening 310, the external input and output terminal 210 connected to theinterconnection part 211 is exposed outside.

The PCM case may be mounted to the battery cell in a state in which theopening faces upward as shown in FIG. 1 or in an arrow direction asshown in FIG. 5. Also, the PCM case may be mounted to the battery cellin a state in which the board is perpendicular to the battery cell aswell as in a state in which the board is parallel to the battery cell,as previously described.

Referring to FIG. 6 together with FIGS. 1 and 8, the anode terminal 120and the cathode terminal 110 are bent toward one face of the batterycell at which the sealed surplus portion 130 is formed so that the PCMcase 300 is mounted to the sealed surplus portion 130 of the batterycell 100.

When the PCB 200 is mounted to the sealed surplus portion 130 formed atone face of the battery cell 100 as described above, the PCB 200 ismounted perpendicularly to the sealed surplus portion 130. In a case inwhich it is difficult for the sealed surplus portion 130 to have asufficient size, therefore, the size of the PCB 200 may be reduced.

Referring to FIGS. 7 and 8 together with FIG. 10, the PCM case 300, inwhich the board is disposed, is opened at one face thereof. Aspreviously described in connection with FIG. 1, the open face of the PCMcase 300 may be closed by the electrically insulative lid 600. Also, asshown in FIG. 7, the electrically insulative lid 600 is provided withthe hooks 610 corresponding to the fastening grooves 320 of the PCM case300, and the PCM case 300 is provided with the fastening grooves 320corresponding to the hooks 610 of the electrically insulative lid 600.Consequently, the PCM case 300 and the electrically insulative lid 600may be coupled to each other through an assembly type fasteningstructure.

Also, the position and shape of the fastening grooves and fasteningprotrusions (for example, hooks) are not particularly restricted so longas the PCM case and the lid are coupled to each other by the fasteninggrooves and the fastening protrusions.

FIG. 9 is a view showing a state in which a label 400 covers the PCMcase 300 and the battery cell 100 in a state in which the PCB 200mounted to sealed surplus portion 130 of the battery cell 100 isdisposed in the PCM case 300. The label 400 according to the presentinvention may be configured to cover the outer faces of the PCM case 300and the sealed outer circumferences of the battery cell 100 (see arrowdirections in FIG. 9) so that the external input and output terminal canbe exposed outside. For example, as shown in FIG. 9, the label 500 maybe attached to cover the outer faces of the PCM 500 and the sealed outercircumferences of the battery cell 100 excluding the external input andoutput terminal 210 exposed outside.

In a case in which the label 400 is attached to the battery cell, it ispossible to stably fix the sealed outer circumferences of the batterycell to the main body of the battery cell while maintaining the overallinsulation state, thereby more stably securing the electrical connectionstate between the electrode terminals of the battery cell and the PCB.

FIG. 11 is a perspective view of a secondary battery pack according toanother embodiment of the present invention configured so that anexternal input and output terminal is mounted to a PCB. Referring toFIG. 11, as previously described, a secondary battery pack 800 isconfigured to have a structure in which an external input and outputterminal 430 is formed at one face of the PCB (not shown) so that theexternal input and output terminal 430 is exposed outside through a PCMcase 420.

As is apparent from the above description, the secondary battery packaccording to the present invention is configured so that the PCM 500, inwhich the protection circuit board electrically connected to the cathodeterminal and the anode terminal of the battery cell is disposed in thecase, is mounted to the sealed surplus portion formed at one face of thebattery cell. Consequently, it is possible to effectively protect thePCM and to greatly reduce the number of parts constituting the secondarybattery pack, thereby greatly improving manufacturing efficiency, ascompared with the conventional secondary battery pack.

Also, the secondary battery pack according to the present invention isconfigured so that the protection circuit board is disposed in theelectrically insulative case. Consequently, it is possible to protectand insulate the PCM including the protection circuit board. Also, it ispossible to easily prevent the electrode terminals from being exposedoutside without insulation of the electrode terminals through the use ofadditional members.

Furthermore, the secondary battery pack according to the presentinvention is configured so that the protection circuit board is mountedin the case. Consequently, it is possible to easily manufacture thesecondary battery pack, to relatively reduce a defect rate, and toconfigure the secondary battery pack so that the secondary battery packhas no wrinkles formed at the outer face thereof, i.e. a neat and cleanexternal appearance, as compared with the conventional secondary batterypack in which the PCM is insulated using a tape.

In addition, the secondary battery pack according to the presentinvention is configured so that the protection circuit board is mountedto the sealed surplus portion formed at one face of the battery cell.Consequently, it is possible to reduce the length of the sealed surplusportion and to increase the capacity of the battery pack per unitvolume, as compared with the conventional secondary battery pack.

Meanwhile, in a general process of assembling the secondary batterypack, the connection members and the PCM are coupled, and an insulativetape is attached at each step, to the PCM assembly is mounted to thebattery cell, as previously described. That is, the PCM assembly ismounted to the battery cell using a plurality of parts with the resultthat a plurality of processes is required, and structural stability aswell as mechanical strength is low.

On the other hand, the protection circuit module according to thepresent invention is configured to have a structure in which theprotection circuit board is mounted in the case, and therefore, it ispossible to improve structural stability of the battery pack, to greatlysimplify the process of manufacturing the battery pack, to secureexcellent insulativity, and to maximize the capacity of the battery cellin the battery pack having the same standard as the conventional batterypack.

Also, in the manufacturing method according to the present invention, itis possible to protect and insulate the PCM using the case without anadditional member, such as a label or an insulative tape. Also, theprotection circuit board is electrically connected to the electrodeterminals, the electrode terminals are bent, and then the protectioncircuit board is mounted in the case with the result that no exposedregion is formed during the bending process, and therefore, anadditional insulative member is not required.

Although the exemplary embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims.

The invention claimed is:
 1. A secondary battery pack comprising: abattery cell having an anode terminal and a cathode terminal formed atone face having a sealed surplus portion; and a protection circuitmodule (PCM) electrically connected to the battery cell via the anodeterminal and the cathode terminal, wherein the PCM comprises: a boardhaving a protection circuit formed thereon, the board being providedwith an anode terminal connection part and a cathode terminal connectionpart connected to the anode terminal and the cathode terminal,respectively; and a PCM case configured to receive the board through anopen face thereof so that the PCM case surrounds the board, the PCM casehaving a bottom wall extending parallel to the anode terminal and thecathode terminal, a first side wall extending from a first edge of thebottom wall, a second side wall extending from a second edge of thebottom wall, and a first end wall and a second end wall extendingbetween the first side wall and second side wall, wherein the board iscoupled to the anode terminal and the cathode terminal of the batterycell via the anode terminal connection part and the cathode terminalconnection part, the board is disposed in the PCM case in a state inwhich the board is parallel to the battery cell, and the PCM case, inwhich the board is disposed, is mounted to the sealed surplus portion ofthe battery cell in order to make the board vertically mounted to thesealed surplus portion of the battery cell, wherein the anode terminalconnection part and the cathode terminal connection part extend along anouter surface of the second side wall of the PCM case, wherein the PCMfurther comprises an electrically insulative lid to close the open faceof the PCM case, wherein the board further comprises an external inputand output terminal, wherein the external input and output terminal isformed at the board at which the anode terminal connection part and thecathode terminal connection part are formed via an interconnection partconnected to one end of the board, wherein the PCM case furthercomprises an opening, through which the external input and outputterminal is drawn, formed at a face adjacent to the open face thereofcorresponding to the interconnection part, the interconnection partextending through the opening so that the external input and outputterminal is outside the PCM case, wherein the opening is a slit typeopening, wherein the anode terminal connection part and the cathodeterminal connection part respectively include a part coupled to the PCBand an extension part configured to be bent when the anode terminalconnection part and the cathode terminal connection part are connectedto the anode terminal and the cathode terminal of the battery cell,respectively, and wherein the secondary battery pack further comprises anickel plate additionally mounted to one face of the cathode terminal,to which the cathode terminal connection part of the board is coupled.2. The secondary battery pack according to claim 1, wherein the PCM caseand the lid are coupled to each other through an assembly type fasteningstructure.
 3. The secondary battery pack according to claim 2, whereinthe PCM case is provided with at least one fastening groove for couplingwith the lid, and the lid is provided with at least one fasteningprotrusion corresponding to the at least one fastening groove of the PCMcase.
 4. The secondary battery pack according to claim 1, wherein thebattery cell is a plate-shaped battery cell, and the anode terminal andthe cathode terminal are plate-shaped conductive members.
 5. Thesecondary battery pack according to claim 1, further comprising aninsulative tape additionally attached to an electrode terminal exposureregion of the sealed surplus portion.
 6. The secondary battery packaccording to claim 5, wherein the insulative tape is a double-sidedtape.
 7. The secondary battery pack according to claim 1, furthercomprising an insulative tape additionally attached to at least one ofouter faces of the PCM case.
 8. The secondary battery pack according toclaim 1, wherein the battery cell is configured to have a structure inwhich an electrode assembly, comprising cathodes, anodes, and separatorsrespectively disposed between the cathodes and the anodes, is disposedin a battery case made of a laminate sheet comprising a metal layer anda resin layer in a sealed state.
 9. The secondary battery pack accordingto claim 1, wherein the board is disposed in the PCM case in a state inwhich the board is parallel to the battery cell in an extensiondirection identical to an extension direction of the sealed surplusportion.
 10. The secondary battery pack according to claim 1, furthercomprising a label to cover the battery cell.
 11. The secondary batterypack according to claim 10, wherein the label is configured to have astructure to cover sealed outer circumferences of the battery cell. 12.The secondary battery pack according to claim 1, further comprisingnotches in a top edge of the second side wall of the PCM case, thenotches aligned with the anode terminal connection part and the cathodeterminal connection part to allow connection with the board inside thePCM case.
 13. The secondary battery pack according to claim 1, whereinthe second side wall of the PCM case is further from the anode terminaland the cathode terminal than the first side wall of the PCM case.